JPH0491A - Hose connection structure - Google Patents

Abstract

PURPOSE:To reduce the number of work processes and reduce generation of mistakes by inserting the nipple part of a joint part into a hose for fastening it with the fastening part, engaging a pipe with the engaging part of the joint, pressure contacting the fore end part of the pipe with the inner circumferential face of the hose to carry out sealing. CONSTITUTION:An engaging protrusion 6 is formed on a pipe 1 to fit in an engaging recess 9 of an engaging part 3. After an end part of a hose 2 is widened in its diameter, a nipple part 8 of a joint 4 is inserted therein and fastened by a fastening part 5. In this case the engaging part 3 is provided with a slit to facilitate the engagement of the projection 6. Also a protrusion is provided on the nipple part 8 to enable connection with the inner face of the hose 2. The outer diameter of the tip of the pipe 1 is enlarged more than the inner diameter of the hose 2, and then the hose 2 is inserted, and thereby the hose 2 is pressure contacted to enable sealing. Consequently the engagement of projection with the recess control movement in the axial direction with a high performance sealing. Furthermore, the number of work processes is reduced so that generation of mistakes is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a hose connection structure for connecting a hose and a pipe used in automobiles and the like to transfer fluid.

[Conventional technology 1 Conventionally, the boss connection structure used in low-pressure fluid circuits for automobiles involves inserting a pipe into a rubber hose and then tightening and fixing the hose with a clamp or clip to prevent the hose from falling out when pulled out from the pipe. This has been prevented (Utility Model Application No. 165185/1985).

Conventionally, in these hose connection structures, as shown in FIG.
The bulging convex portion 21 presses the inner peripheral surface of the hose 23 to tightly seal the hose 23, and the outer peripheral surface of the hose 23 is tightened with a wire clamp 24 or a leaf spring clip 25 to connect the hose 23 to the pipe 20. It has become established.

[Problems to be Solved by the Invention] However, in the above-mentioned hose connection @ construction, the outside diameter of the pipe that is press-fitted is larger than the inside diameter of the hose in order to maintain sealing performance, and the pipe is provided with a protrusion. The workability of inserting the pipe into the hose is poor. Therefore, it is difficult to adjust the insertion distance of the pipe to a constant value, and the insertion distance tends to vary. When tightening the hose by tightening the outer surface of the hose with a rough clip or metal hunt, tighten it while preventing the hose from being handled. The sealing performance of the connection and handling strength tend to vary depending on the position, tightening torque, etc.

Automation of this assembly is being considered in order to improve work efficiency, but this is difficult to apply with the above hose connection structure.

The present invention was made in view of the above circumstances, and aims to provide a hose joint structure that improves the workability of assembly and stabilizes connection quality such as sealing performance and handling strength of hose tightening parts. shall be.

[Means for Solving the Problems] The hose connection structure of the present invention includes an engaging part having a first engaging part on the inner circumferential surface, and a nipple part extending in the axial direction from the engaging part and being inserted and coupled to the hose. a fastening part that fastens the outer peripheral surface of the end of the hose together with the joint part to which the hose is coupled, and a second engaging part that engages with the first engaging part on the outer peripheral surface.
It has an engaging part and is inserted into the joint part from the cough engaging part side.
The engaging portion is engaged with and held by the first engaging portion, and
The distal end portion is a pipe that protrudes from the nipple portion into the hose, and the inner diameter of the hose at least in the portion facing the outer circumferential surface of the distal end portion is smaller than the outer diameter of the distal end portion, and the inner diameter of the hose is smaller than the outer diameter of the distal end portion. A sealing portion is formed by pressure contact between the surface and the outer circumferential surface of the tip portion.

This hose connection structure consists of a joint part in which an engaging part and a nipple part are integrally formed, a hose into which the nipple part is inserted and connected, and a fastener that fastens the outer peripheral surface of the end of the hose together with the joint part. It consists of a fitting part and a pipe connected to a joint part.

This joint part is constructed by integrally forming an engaging part having a first engaging part that engages a pipe and a nipple part that engages a hose.

A first engaging portion is formed on the inner circumferential surface of the engaging portion, and engages with a second engaging portion provided on the pipe to fix the pipe and restrict movement in the axial direction. The first engaging part has, for example, a ring-shaped recess formed entirely or partially on the inner circumferential surface of the engaging part, and is formed in a shape that can be elastically deformed in the direction of diameter expansion, and is formed on the surface of the pipe. Even if a protrusion shape such as a second engaging portion is formed on the pipe, the pipe can be easily inserted.

This engaging part facilitates elastic deformation, for example,
The workability of inserting the pipe can be improved by making it made of resin and providing a plurality of slits in the axial direction from the end, or by appropriately designing the wall thickness.

In addition, the convex second engaging part formed on the pipe surface is engaged with the hook-shaped groove formed on the inner circumferential surface of the engaging part by turning it at the insertion position. The connecting and fixing work is facilitated by engaging with the second engaging portion.

It is desirable that the nipple part extends from the engaging part toward the hose, and has an outer diameter larger than the inner diameter of the hose, and is formed on the outer circumferential surface in the form of a plurality of serrated protrusions or rings that connect the hoses. This serrated protrusion further improves the bonding strength of the hose end.

The fastening part covers the outer peripheral surface of the hose coupled to the nipple part and fastens the hose together with the joint part. This fastening portion can be formed into a rib shape by molding a resin. Alternatively, it may be formed from a metal member such as a leaf spring clip or a wire clamp. In the case of molding, the clamping force is even stronger due to the molding pressure during molding and the shrinkage force of the resin material. It is also possible to tighten the hose by extending the fastening part like a sleeve in the axial direction from the joint part, thereby reducing the inner diameter of the hose to be smaller than the outer diameter of the pipe to improve the sealing performance of the sealing surface. can. Therefore, the end of the hose is expanded in diameter and locked by the nipple part, and is firmly fastened to the joint part by the fastening part.

The pipe extends from the coupled portion of the hose, and a second engagement portion coupled to the first engagement portion of the engagement portion is formed on the outer circumferential surface of the pipe by bulging or the like. The tip portion extending from the second engaging portion projects from the nipple portion. This tip portion comes into pressure contact with the hose to form a seal. That is, for example, a hose whose inner diameter is smaller than the outer diameter of the pipe can be used. Further, when forming the fastening portion, external pressure may be applied to the hose to reduce its diameter, thereby reducing the inner diameter of the portion of the hose that faces the tip portion. As a result, when the pipe is press-fitted into the hose, the outer circumferential surface of the distal end portion of the pipe comes into pressure contact with the inner circumferential surface of the hose to form a seal portion. Further, a bulge may be provided at the tip of the pipe to further improve sealing performance. Note that even if the inner diameter of the hose is smaller than the outer diameter of the tip of the pipe, the pipe is guided by the joint and press-fitted into the hose during insertion, so the insertion load can be reduced.

In order to improve the sealing performance, it is preferable that the length of pressure contact between the pipe end portion and the hose in the axial direction in the seal portion is at least 5#1 or more.

The axial movement of the pipe is restricted by the engagement of the second engaging part with the first engaging part, and the pipe is brought into pressure contact with the hose at the sealing part, thereby forming a sealed hose connection structure.

Furthermore, an O-ring may be inserted between the outer circumferential surface of the pipe and the inner circumferential surface of the nipple portion to further improve the sealing performance of the connection structure.

[Function] As described above, in the hose connection structure of the present invention, the diameter of the hose is expanded at the nipple portion and fixed by the hose's own binding force, and the tightening portion prevents the hose from expanding in diameter. It remains fixed in place. In addition, the hose is firmly fixed to the joint due to the torque of the fastener of the fastening part or the shrinkage force during molding, thereby preventing handling.

The engaging part of the joint part is pressed by the engaging convex part when the pipe is inserted, expands in diameter, and is fixed to the pipe or the joint part by engaging when the second engaging part reaches the first engaging part. In addition, since the inner diameter of the hose is smaller than the outer diameter of the distal end of the pipe, the outer circumferential surface of the hose comes into pressure contact with the inner circumferential surface of the hose to form a sealed portion.

[Example] Hereinafter, this will be explained in detail using examples.

(Example 1) This example will be explained based on FIG. 1. This boss connection structure is composed of a pipe 1, a hose 2, a joint part 4, and a fastening part 5.

The pipe 1 is formed with a ring-shaped engagement convex portion 6 that bulges on the outer circumferential surface.

The end of the hose 2 is expanded in diameter and inserted into a joint portion 4 having an outer diameter larger than the inner diameter of the hose 2.

The joint part 4 consists of a large-diameter engagement part 3 and a small-diameter nipple part 8 coaxial with the engagement part 3, and is integrally formed from resin. The engaging portion 3 can be elastically deformed in the direction of expanding its diameter, and a ring-shaped engaging recess 9 is provided on the inner circumferential surface.

As shown in FIG. 2, the engaging part 3 is provided with a plurality of slits 10 in the axial direction from the end to prevent the diameter of the engaging part 3 from expanding due to the insertion load of the engaging projection 6 when the pipe 1 is inserted. In addition to increasing the elasticity of the resin, it facilitates recovery after deformation.

The nipple portion 8 extends from the engaging portion 3 and is coupled to the inner circumferential surface of the hose 2 by forming a plurality of ring-shaped protrusions in the shape of saw blades larger than the inner diameter of the hose on the outer circumferential surface.

The fastening part 5 is formed into a sleeve shape of resin by molding so as to cover the hose 2 coupled to the nipple part 8, and fastens the hose 2.

The inner diameter of hose 2 is smaller than the outer diameter of pipe 1;
The pipes 1 and 2 are tightly connected to the fitting part 3 and the hose 2 to the joint part 4 by the nipple part 8 and the fastening part 5, respectively. .

The pipe 1 can be made of aluminum, STKMIIA or galvanized metal.

The hose 2 can be made of full rubber, intermediate braid, or outer braid.

In the joint part 3, the engaging part 4 and the nipple part 8 are integrally molded with resin, and are made of nylon (6-nylon, 6°6-nylon, 11-nylon, 12-nylon, etc.), polyester (PET, PBT, etc.). ), polyolefins such as polyethylene and polypropylene are used.

The fastening part 5 is formed by placing the joint part 4 together with the hose 2 coupled to the nipple part 8 in a mold, and by injection molding or the like. This resin may be the same as that of the joint portion 4 or may be different. Resins include nylon, polyester,
Polyolefin, PP5 (polyphenylene sulfide), PEEK (polyetherketone), etc. are used.

To connect the pipe 1 to the hose 2, first connect the end of the rubber hose 2 to the nipple part 8 of the joint part 4 made of 6-nylon.
The diameter of the fastening part 5 is expanded and joined, and the fastening part 5 is molded with 6-nylon to fasten it. Next, the joint part 4 where the hose 2 is fastened
Insert the pipe 1 into the engaging part 3. Here, the outer diameter of the pipe 1 is approximately the same as the inner diameter of the joint portion 4 and larger than the inner diameter of the hose 2. When this pipe 1 is inserted into the engaging part 3, the engaging convex part 6
expands the diameter of the fastening portion 3, and upon engagement with the engagement recess 9, the fastening portion 3 is restored to its original shape by elastic force. At this time, the tip portion of the pipe 1 is press-fitted into the hose 2 to form a sill portion 7.

When the pipe 1 and the hose 2 are to be joined together, the joining work is facilitated by simply inserting and tightening without adjusting the torque or adjusting the insertion distance.

Therefore, the pipe 1 can be easily connected to the hose 2 by being guided by the joint part 4, and the assembly can be automated.

The pipe 1 is engaged with the engagement concave portion 9 of the engagement portion 3 through the engagement convex portion 6, and is in pressure contact with the hose 2 at the seal portion 7, so that the sealing performance and centering strength can be made constant.

On the other hand, since the hose 2 is also fastened by the joint part 4, a hose connection structure with high bow handling strength can be formed.

(Example 2) In this example, in order to further improve the sealing performance of the hose connection structure, as shown in FIG. It is the same as Example 1. That is, two O-rings are placed at intervals on the inner circumferential surface of the nipple portion 8, and one O-ring is placed on the inclined surface of the engagement convex portion 6.
The ring was placed. The O-ring 11 not only allows the hose 2 and the pipe 1 to be closely sealed at the seal portion 7, but also allows the inner circumferential surface of the nipple portion 8 and the pipe 1 to be airtightly sealed by the O-ring 11.

Therefore, even if the area of the seal portion 7 of the pipe 1 is small, the sealing performance will not deteriorate. Furthermore, the inner diameter of the joint portion 4 does not have to be approximated to the outer diameter of the pipe 1, which makes the connection work easier.

(Example 3) In this example, the fastening part 5 was not molded with resin as shown in FIG. 4, but was crimped with a metal band to fasten the hose 2 to the nipple part 8. Same as Example 1. The hose 2 can be securely fastened to the joint part 4 by the caulking torque of this metal band. Further, since the hose 2 can be fastened to the joint portion 4 without molding, the degree of freedom in work is increased.

(Embodiment 4) In this embodiment, the fastening part 5 is connected to the hose 2 as shown in FIG.
This is the same as in Example 1 except that the resin is extended into a sleeve shape beyond the enlarged diameter portion of the hose 2 to form the original outside diameter of the hose 2.

As a result, the tightening force of the hose 2 is increased, and the sealing performance between the hose 2 and the pipe 1 at the seal portion 7 can be improved.

(Example 5) In this example, as shown in FIG. 6, before forming the fastening part 5 with resin, the metal ring 12 for temporary fixing is caulked in advance to connect the hose 2 to the nipple part 8. , is the same as Example 1 except that it is placed in a mold and molded into a sleeve shape with resin. Therefore, the hose 2 is even more firmly attached to the nipple portion 8.
It is fastened to. In addition, the metal ring 12 is used to tighten the fastening portion 5.
The fastening portion 5 can be prevented from rotating by being fixed from the inner peripheral surface side.

In addition, a recessed part 13 for adjusting the insertion load is formed on the outer peripheral surface of the engaging part 3 in the resin of the joint part 4 to adjust the wall thickness of the engaging recess 9, thereby improving the workability of inserting the pipe 1. .

(Embodiment 6) This embodiment is a connection structure in which only the inner diameter of the seal portion of the hose is reduced to be smaller than the outer diameter of the pipe when forming the fastening portion.

In this hose connection structure, as shown in FIG. 7, first, an inner mold 15 having the same outer diameter as the pipe 1 is inserted into the joint 4 to which the hose 2 is connected. The tip of the inner mold 15 is inserted into the hose 2, and the outer diameter of the tip portion is smaller than the inner diameter of the hose 2. This is fixed at a predetermined position on the outer mold, and a fastening part 5 is formed on the outer peripheral surface of the end of the hose 2 by resin molding.

In this case, the inner diameter of the portion of the outer mold facing the tip of the inner mold 15 is smaller than the outer diameter of the hose, and the fastening portion 5 is formed with the hose 2 reduced in diameter at that portion.

Once the pipe 1 is inserted, the distal end portion of the pipe 1 comes into pressure contact with the reduced diameter portion of the hose 2, forming a seal portion 7.

In this connection structure, even if the hose 2 has an inner diameter larger than the outer diameter of the pipe 1, the same effect as in the first embodiment can be obtained.

In addition, the hose 2 can be easily inserted into the nipple portion 8, and a wide flow path can be secured.

(Embodiment 7) In this example, as shown in FIGS. 8 and 9, after reducing the diameter of the hose 2 with the ring-shaped rigid member 14, the rigid member 14
This is the same as in Example 1 except that the fastening portion 5 is formed to cover the. By using this rigid member 14, it is possible to prevent a decrease in the fastening force due to sagging of the resin of the fastening portion 5, and to maintain the tight sealing performance for a long period of time. Particularly when used for a long time at high temperatures, the fastening portion 5 tends to become sagging, but this can be prevented by providing the rigid member 14. Also, stress cracks in the fastening portion 5 can be prevented.

In this case, the rigid member 14 may be covered with the fastening portion 5 or may be uncovered and exposed. Note that the rigid member 1
4 is preferably covered with a fastening portion 5, since handling in the axial direction can be prevented.

According to this connection structure, durability is greatly improved compared to the structure of the fourth embodiment.

[Effects] According to the hose connection structure of the present invention, the axial movement of the pipe is regulated by the engagement between the engagement protrusion and the engagement recess, and the seal portion presses against and closely contacts the hose, resulting in high sealing performance. It has a connection structure.

This connection work can achieve both fixing and sealing in the step -. Furthermore, the pipes can be connected simply by inserting the pipes to the specified positions. Therefore, there is no need to adjust the insertion distance. Further, since the hose is previously tightened by the joint part and the fastening part, there is no need to adjust the torque for tightening a clip or the like to stop handling the hose when the hose and pipe are connected. Therefore, it is possible to reduce man-hours, reduce assembly defects, and reduce human errors. Therefore, the process becomes simple and automation is possible.

Further, the insertion load when inserting the pipe can be appropriately selected by selecting the rigidity of the material of the engaging portion and changing the slit width, length, number, etc.

[Brief explanation of drawings]

1 is a cross-sectional view showing the hose connection structure of Example 1, FIG. 2 is a front view of the hose connection structure of Example 1, and FIG. 3 is a cross-section view of the hose connection structure of Example 2. 4 is a sectional view showing the hose connection structure of Example 3, FIG. 5 is a sectional view showing the hose connection structure of Example 4, and FIG. 6 is a sectional view of the hose connection structure of Example 5. FIG. 7 is a schematic cross-sectional view showing the state inside the mold for forming the hose and joint part of Example 6, and FIG. 8.9 shows the hose connection structure of Example 7. It is a cross-sectional view, and the 10th
The figure is a sectional view showing a conventional hose connection structure. 1... Pipe 3... Engaging part 5... Fastening part 7... Seal part 9... Engaging recess 11... O-ring 13... Recessed part 2... Hose 4 ...Joint portion 6...Engaging convex portion 8...Nipple portion 10...Slit 12...Metal ring 14...Rigid member patent applicant Toyoda Gosei Co., Ltd.

Claims (1)

[Claims] (1) A coupling part consisting of an engagement part having a first engagement part on the inner circumferential surface and a nipple part extending in the axial direction from the engagement part and inserted and coupled to the hose, and the coupling part to which the hose is coupled. and a second engaging part that engages with the first engaging part on the outer peripheral surface, and is inserted into the joint part from the engaging part side. The second engaging portion is engaged with and held by the first engaging portion, and the distal end portion is a pipe protruding from the nipple portion into the hose, and at least the outer circumferential surface of the distal end portion is A hose characterized in that the inner diameter of the opposing portion of the hose is smaller than the outer diameter of the tip portion, and a seal portion is formed by pressure contact between the inner circumferential surface of the hose and the outer circumferential surface of the tip portion. Connection structure.